Forum adverts like this one are shown to any user who is not logged in. Join us by filling out a tiny 3 field form and you will get your own, free, dakka user account which gives a good range of benefits to you: No adverts like this in the forums anymore. Times and dates in your local timezone. Full tracking of what you have read so you can skip to your first unread post, easily see what has changed since you last logged in, and easily see what is new at a glance. Email notifications for threads you want to watch closely. Being a part of the oldest wargaming community on the net. If you are already a member then feel free to login now.

How many shots to kill one with str 6-8 / grav guns?

Thanks


Automatically Appended Next Post:
Without D weapons

Strength of grav guns doesn't matter because of their unique properties. They wound a C'Tan on a 3+ then he gets 4++, then FNP, then it will not die, then blows up with 4d6" str10 ap1 radius of pain.

How many shots per to take one down though?

This is where math would come in handy...

I don't remember C'tan stats off the top of my head, but...
-2/3 hit
-2/3 wound
-1/2 are saved
-1/3 are FNP'd

So for each shot you've got about a 7% chance to knock off a wound. A unit of 3 Grav Centurions has 15 shots so you'll take off... 1 wound on average if my math is correct. Good luck.

How many wounds?

 Desubot wrote:
How many wounds?

6 Wounds, T9, 3+ save, 4++ invul, Fnp and IWND.

You can get around IWND by nuking it in 1 turn.
No getting around the FnP or the invul if we aren't allowed D weapons.
Toughness can be worked around with Grav weapons, but Gargantuan Creatures are only wounded by "wounds on X+" on a 6 (I think).

Average lascannons shots to kill (BS4, no cover); 54
Missiles; 81
Autocannon shots; 244 (122 autocannons)

etc.

Basically, 3000+ points of concentrated fire power, which is almost impossible to bring to bare against something this size. Either use "D" weapons, or chip away at it and pray it doesn't roll well on IWND

Andilus Greatsword wrote:
-2/3 hit
-2/3 wound
-1/2 are saved
-1/3 are FNP'd

If this is the case, it takes 81 shots, with average rolling.

Carnage43 wrote:
Toughness can be worked around with Grav weapons, but Gargantuan Creatures are only wounded by "wounds on X+" on a 6 (I think).

But if this is correct, it takes 324 shots.

I think gravs still wound on the 3+ for the armor save and its just poison weapons that are a 6+ .... think my plan is going to run a 4 grav command squad / 3 grav bike squads (sgt with combi / 2 gravs) and 3 melta bike squads with some storm talons & other support. I might add in a librarian with telepathy (for shriek / puppet master) and 5 sternguard with combi-gravs.

I think on average it will take 14 regular grav guns (if they wound on 3+) shooting to down it in one turn (ill have 18 with all the gravs and combis combined), the main problem is that with double waves of withering if the c'tan isn't taken out in one turn almost all of my force is going to be taken out with the size of the D templates.

Right now I don't think anyone else is going to be running anything with D weapons besides knights and I doubt anyone has the money atm to shell out for a super heavy (multiplayer game 2-3 people per side not sure on exact points atm probably 2000 per).

Thoughts?

I checked the book it only is effected by poison and sniper

with grav guns assuming no cover.

it takes 41 shots from a marine to kill it one turn.

41 shots > 27.333 hits > 18.222 wounds > 9.111 failed invul > 6.07 failed FNP = one dead ctan shard.

 Whereswaldo wrote:
I think on average it will take 14 regular grav guns (if they wound on 3+) shooting to down it in one turn (ill have 18 with all the gravs and combis combined), the main problem is that with double waves of withering if the c'tan isn't taken out in one turn almost all of my force is going to be taken out with the size of the D templates.

Well my math was on Grav Cannons, so 15 shots per unit of Centurions knocks off 1 wound. So to take off all 6 in one turn you need almost 90 Grav weapon shots.

You guys are not forgetting reroll to wound from grav amp right? Or potential reroll hits from lets say chapter tactics or preferred enemy.

 pizzaguardian wrote:
You guys are not forgetting reroll to wound from grav amp right? Or potential reroll hits from lets say chapter tactics or preferred enemy.

Oh, I didn't realize they got a reroll to wound. I don't have the SM Codex, but no one else felt like doing mathhammer (including the OP).

In that case, I believe 8/9 will wound if my math is correct. There's also probably some prescience going on, but I'll ignore it since it was never explicitly mentioned. That puts us up to about a 10% chance of wounding, so I believe you need just over 60 heavy grav cannon shots to take it down. Someone might want to double-check my math though.

 pizzaguardian wrote:
You guys are not forgetting reroll to wound from grav amp right? Or potential reroll hits from lets say chapter tactics or preferred enemy.

Well i left it bare minimum as they could be running around on grav bikes too.

 Desubot wrote:

 pizzaguardian wrote:
You guys are not forgetting reroll to wound from grav amp right? Or potential reroll hits from lets say chapter tactics or preferred enemy.

Well i left it bare minimum as they could be running around on grav bikes too.

True, but on battle conditions ctan has a longer engagement range then grav bikes, if not coming from reserves or first turn. (33" for ctan to 30" for bikes)

And that's why in my area it is theory crafted to drop centurions from a stormraven to get the first shot. To my calculations they will do 2.96 wounds on ctan without any sort of rerolling hit.

15 shots x 2/3 hit x 8/9 wound x 3/6 invul save x 2/3 fnp.

If there is preferred enemy (or any reroll hit of just 1) the wounds increase to 3.45. And if you reroll all to hit(although how you do this on the turn you arrive elludes me) you get 3.95 unsaved after everything.

It should take ~30 shots from grav centurions to kill it.

30
x2/3 (To Hit: 3+) = 20
x8/9 (To Wound 3+ rerollig failed) = 17.8
x1/2 (4+ Invulnerable save) = 8.9
x2/3 (5+ FnP) = 5.9

So a group of 6 centurions gate of infinitied within range
or 2 groups of 3 centurions skies of furied from 2 stormravens
or get prescience from tiggy;
23
x8/9 (To Hit: 3+ reroll) = 20.4
x8/9 (To Wound 3+ rerollig failed) = 18.1
x1/2 (4+ Invulnerable save) = 9.1
x2/3 (5+ FnP) = 6

The only problem with all of this is that these are averages which means you are as likely to kill him as to leave him wounded but alive. You had better plan for a 2 wound deviation and have something extra to finish the job as grav weapons are a high risk strategy to kill him.

The most sure fire method to kill a GMC I have seen is a 6 centurion star with loth or tiggy (gate of infinity) and buff commander (reroll misses and ignore cover). As long as you can stay out of LoS and range you will almost assuredly get the drop and murder it. (that is an average of 8 wounds or 9 with missiles)

 ansacs wrote:
The only problem with all of this is that these are averages which means you are as likely to kill him as to leave him wounded but alive. You had better plan for a 2 wound deviation and have something extra to finish the job as grav weapons are a high risk strategy to kill him.

This is what I was just going to mention. There are more complicated mathematical ways of figuring out how many shots to kill it with an x% probability, but they are a very much harder to do on the fly and to be honest serious statistics was always a weak point of mine so I couldn't tell you what the best way to go about it would be.

Anything you get out of regular Mathhammer should basically be assumed as 50% reliable. Half the time you'll get that many or more wounds. Half the time you'll get less. Always best to pack enough firepower for 1-2 "extra" wounds to pad out the probability more in your favor.

I played my C'Tan in a 2000pt gae versus White Scars, who outflanked, emptied everything, failed to kill. I killed about a third in the next turn and then he killed the C'tan - who blew up and killed all but his command squad (who I had killed with despairtek and deathmarks dropping in the sweet spot) and two bikes. I won on objectives with my 15 necron warriors in n scythes. Was actually a super fun game as neither of us had played Escalation stuff before and it wound up being good, silly fun.

I've played 3 games against a C'Tan with my nids, and honestly they were my least favorite games I have ever had in 40k. For however many points it was, it has the ability to murder all of it and negate the majority of my list.
My list: 2 flyrants, 80 terms, venoms, zoanthropes, 3 trygon primes, and some screening horms. Semi-competitve
His list: C'Tan, flying croissants with troops

His C'Tan could Hellstorm D any of my troops (negating my one big advantage of having many more troops than him) and his 6D6 shot just killed any MC that he chose. Combined with the ability to hurt what it moves through, I never even had a chance. After the game, I just packed up and left. I found the one necron list I hate more than flier spam.

Nids kind of get shafted by Apoc in any case though, Biotitans are overpriced when D-weapons can take them out in a couple shots.